Food Spoilage Monitoring Device

ABSTRACT

An activatable spoilage monitoring device ( 2 ) is housed in a lid for a container. The device comprises a resevoir containing a digestor fluid and a tray ( 62 ) containing a digestible material or gel and having a tactile pattern of protuberances ( 68 ) formed in a base of the tray. The two parts ( 4, 6 ) of the lid axially compress together as the lid is opened resulting in activation of the device by permitting the fluid to come into contact with the digestible material.

TECHNICAL FIELD

The present invention relates to the technical field of monitoring theshelf life of food products, particularly beverages and other bottledproducts.

PRIOR ART

An approach to food spoilage monitoring is described in U.S. Pat. No.9,915,638 13 Mar. 2018 (PAKSTAITE) which provides a monitoring device inthe form of a label that offers a tactile response indicating foodspoilage when a layer of material above a bumpy or ridged surface hasliquefied. Synchronising the phase transition of the material with therate of spoilage of the packaged foodstuff allows a more efficientindication of food quality than the traditional best before datemarking. This is because the label and the food product are subject tothe same environmental conditions during transit and storage.

TECHNICAL PROBLEMS

However, some products will only start the decay or spoilage processafter a package has been opened. In some products opening willaccelerate the decay or spoilage process. Therefore, there is atechnical problem in monitoring this, as it then becomes necessary toactivate the label so that it replicates the same conditions as theproduct only after activation. There is therefore a technical problem inproviding for activation on opening of a package.

When using a tactile sensing device, it is necessary for the device tobe supported on the packaging such that it can be felt easily withoutinterference from other responses generated by the packaging. There istherefore a technical problem in providing support for the device.

The present invention therefore addresses the above described technicalproblems.

SOLUTION OF THE PRESENT INVENTION

The present invention is defined in the appended claims.

Many beverages and food products are packaged in bottles which use astandard screw cap or lid closure and embodiments of the presentinvention are designed to be incorporated into such a lid. Preferablythe device is activated using the same motion that is necessary to openthe lid of the container. The device can be supported within the lidwhich typically already has a sufficiently rigid underlying surface.This facilitates reliability and the use of the tactile monitoringdevice.

DESCRIPTION OF THE DRAWINGS

In order that the invention can be well understood some embodimentsthereof will now be described, by way of example only, with reference tothe accompanying diagrammatic drawings, in which:

FIG. 1 shows a cross section through a lid incorporating an activatablespoilage monitoring device in accordance with a first embodiment of theinvention in a pre-activated condition;

FIG. 2 is a cross section through the lid of FIG. 1 after activation;

FIG. 3 is an exploded view showing the component parts of a lidincorporating the device of FIGS. 1 and 2;

FIG. 4 shows a cross section through a lid incorporating an activatablespoilage monitoring device in accordance with a second embodiment theinvention in a pre-activated condition;

FIG. 5 is a cross section through the lid of FIG. 4 after activation;

FIG. 6 is an exploded view showing the component parts of a lidincorporating the device of FIGS. 4 and 5; and

FIG. 7 is a side view of the lid of the first or second embodiment priorto activation; and

FIG. 8 is a cross section on line A-A in FIG. 7 at right angles to thesection shown in FIGS. 4, showing the internal structure of the secondembodiment of the invention and the locked relative position of theparts of the cap before activation.

DESCRIPTION OF AN EMBODIMENT

An activatable food spoilage monitoring device 2 is mounted into anupper part 4 of a two-part cap or lid 6. The lid 6 may be of anystandard size either for fitting to a glass or plastics bottle or jar orany other packaging container having a screw neck. A lower part 8 of thelid 6 has an annular wall component 12 having an internal screw thread10 to engage in a conventional manner with a screw neck. The annularwall component is closed at its upper surface by a recessed top panel14. The top panel 14 has a circular indentation 16 which engages with acorrespondingly shaped circular projection 18 in the upper part. Theprofile in plan of the indentation and projection could take anyappropriate shape provided they match and interlock and permit at leasta limited relative rotation of the indentation and projection. As shownin this first embodiment, the indentation has a circular rib 20 whichsupports a lower wall of the projection 18 which contains the spoilagemonitoring device 2. On the outer side of the wall component 12,oppositely disposed, elongate L-shaped grooves 24 are formed. Thisgroove 24 is best shown in FIG. 3 where its shape can be appreciated.Each groove is designed to cooperate with an inwardly projecting peg 26formed on an inner wall surface of the upper part of the lid. The groovehas an entry section 30 which extends from an intermediate point in thewall to the top panel. The entry section merges with a downwardly slopedtrack 32 so that on rotation of the upper part relative to the lowerpart, the two parts compress together into the configuration shown inFIG. 2. It will be appreciated that more than two guidance grooves couldbe used for larger diameter lids. Alternative guidance systems thatfunction in a similar manner can also be employed.

The upper part 4 of the lid 6 is a cup-shaped member having an annularwall 28 and a top panel 34. The top panel contains the circular shapedprojection 18 which defines within it a recessed cavity 38 into whichthe monitoring device 2 can be received. The cavity has a base 40 whichhas a flexible central portion surrounded by a flexible, peripheral,downwardly-sloped annular wall section 42. As can be seen in FIG. 1,when the device is in a pre-activated condition, the central portion ofthe base 40 is supported on the rib 20 of the indentation 16 in thelower part. Due to the flexibility of the annular ring 42, the centralportion 40 can be inverted or “popped up” in order to activate thedevice when the two lid parts are rotated relative to one another. Inthis first embodiment the annular ring 42 is made of a weakened thinmaterial so that the base can be pushed flat against the bottom of thedevice 2.

The annular wall 28 is provided with two oppositely disposed pegs 26which seat within the grooves 24 of the lower part. The pegs 26 arevisible in FIG. 1. In FIG. 2, the upper part has been rotated relativeto the lower part which forces the upper part downwardly into theconfiguration shown in FIG. 2. During this rotation the central portionof the base will be forced to pop up into the configuration shown inFIG. 2.

The cavity 38 receives the spoilage monitoring device 2. This deviceconsists of a reservoir defined within the bottom of the cavity 38. Thisreservoir contains a digestor fluid or liquid. An insert tray 62 with abase provided with a tactile pattern of protuberances, such as a seriesof ridges or bumps or pimples 68 sits above the reservoir cavity. Thetray receives a layer 64 of a digestible material, for example,gelatine, gel, hydrocolloid or hydrogel. The term gel will be used as ageneric term for this material layer. The gel may contain otherchemicals to moderate its decay process into a liquid. The choice ofdigestor liquid and digestible material is dependent on the contents ofthe product package within the container sealed by the lid. A flexiblefilm 66 seals the device 2 within the cavity 38.

The base of the tray 62 has a central channel 82 which in thepre-activated condition is sealed by a dumbbell shaped rubber valve 90which is push fitted into the channel prior to the introduction of thelayer of digestible gel. The valve 90 has a portion 92 which is retainedbelow the channel and a sealing portion 94 held above it. When the base40 of the recess 38 comes into contact with a lower portion 92 of thevalve, it pushes the upper sealing portion 94 away from the channel 82opening the valve to allow digestor fluid to flow through the channel.

The gel layer 64 has a thin layer of material or cloth 84 at its lowersurface. This cloth could be made of paper or sponge or any otherabsorptive material that is capable of absorbing the digestor liquid inorder to disperse it when it enters the tray on activation.

It is necessary in this embodiment that the sides of the tray are to befitted tightly to the upper part of the cap so that the digester liquidcan only go through the valve seal channel. This tight fit can beachieved by the addition of a snap fit groove 100 around an upperexternal wall of the tray. An inwardly projecting nib 102 is providedaround the upper circumference of the cavity in order to engage with thegroove 100 to seal the device 2 into the cavity 38, in such a way thatany digester liquid in the reservoir cannot escape.

In operation, when the lid is unscrewed in the normal way about an axiswhich is vertical in ordinary use, the first part of the rotation willcause the two parts of the lid to axially compress together reducing thespacing between the two parts. As a result, pressure on the lowerportion of the valve from the base 40 results in the opening of thevalve 90 allowing the digester liquid to be squeezed up and through thechannel 82 onto the bottom of the tray under the gel. The valve 90 canbe made of various different designs. It can be opened eithermechanically by being pushed by the flexible base as described above orbe opened by the increased pressure that is created underneath the traywhen the flexible base is pushed up during activation. Once the digestorliquid is in the tray, the thin cloth 84 absorbs the liquid quickly inorder to disperse the liquid over the entire bottom surface of the gel.The gel then absorbs the digester liquid from the cloth. The clothensures an even spread of the digester liquid over the surface of thegel and prevents the digester liquid from running back under the trayshould the flexible base 40 be re-expanded

Further rotation of the lid will open the container in the conventionalmanner so that the contents can be accessed and the container resealedby reapplication of the lid. The activation process cannot be reversed.The activation process by rotation of the parts is a one-way operationand results in the irreversible chemical activation by the digestorliquid entering the tray. It is desirable to be able to lock theactivation state. This can be achieved by shaping the end of the groove24 to capture the peg and prevent it moving backwards as shown in FIG.3. Activation can also be insured by the interlocking created by thepopping up process of the base 40. Other methods of achieving activationcould be used. Irreversible mechanical activation may be desirablebecause reversal could allow the fluid to come out of contact with thegel to create unreliable results. In other arrangements where theabsorption of the fluid into the gel is sufficient to ensureirreversible activation (that is the chemical reaction is permanent) therotation mechanism can be made reversible, in order to neutralise thepositive pressure in the cap resulting from the initial activationcompression. This makes it easier to feel the bumps once liquefied,because it is less bulgy’. Accordingly the physical mechanism may bereversible; but the activation chemical reaction between the activatorand the gel is irreversible.

As time passes, the digestor liquid is absorbed by the gel and beginsthe temperature dependent decay process which will eventually force thegel to liquefy. When the gel is liquefied, a user touching the film 66will be able to feel the tactile pattern moulded into the base of thetray. When the gel is solid and the contents of the container are stillfresh, the user will feel a smooth surface. Accordingly, the device 2allows the user to detect when the decay process has proceededsufficiently far for the gel to liquefy. By appropriate choice of geland digestor liquid, the decay process in the gel can be made to mimicthe anticipated freshness of the contents of the container.

The film 66 is sealed to the upper part of the lid. Ultrasonic weldingcan be used. Other methods of creating a seal over the sponge could beemployed. The two parts of the lid can be injection moulded plastics.Other forms of fabrication such as vacuum casting could be used. Theoverall height of the lid can be made to match the overall height of aconventional lid so that this type of lid can be simply used in thepackaging process in like for like replacement of conventional screw toplids or caps.

Preferably the outer side of the wall of the upper part 4 is knurled asshown in FIG. 7 to facilitate gripping of the part to initiate rotation.

Second Embodiment

The second embodiment is illustrated in FIGS. 4 to 8 and like parts areindicated by like reference numerals. The general principle of thesecond embodiment is as previously described. In this embodiment thedigestor fluid is contained in a sponge 60 which fills the reservoir 38.The sponge may be made of cellulose or other suitably absorbentmaterial. The type of material used needs to be able to store therequired amount of digestor liquid and expel substantially all of itwhen compressed. As shown in FIG. 4, there are two concentric ribs 20which support the base 40 of the reservoir in this embodiment in orderto create greater force on the sponge 60.

On activation of the device the side wall of the reservoir is popped upinto an inverted position as shown in FIG. 5 to apply uniform pressureto the sponge and cause the digestor fluid to flow around and over theedges of the tray and onto the gel 64. The inversion of the flexiblebase 40 squeezes the digestor liquid out of the sponge, around and overthe sides of the tray and onto the top of the gel layer asdiagrammatically illustrated in FIG. 5, where the digestor liquid isshown as a layer 70 sitting on top of the gel.

The tray 62 could also have perforations in its base to allow entry ofthe digestor fluid squeezed out of the sponge.

It will be appreciated that this embodiment with a sponge in thereservoir could be combined with the first embodiment, with the base ofthe tray provided with a valve sealed channel as in the first embodimentin order to deliver the digestor fluid into a cloth lined base of thetray on activation.

The method of operation of the second embodiment is as previouslydescribed.

1-9. (canceled)
 10. A lid for closing a container comprising a firstpart having an indentation adapted to receive a projection of a secondpart, the projection defining a cavity into which a spoilage monitoringdevice is received; the spoilage monitoring device comprising areservoir containing a digestor fluid and a tray containing a digestiblematerial, wherein the tray has a base with a raised tactile patternformed thereon and the digestible material covers the base with a smoothsurface; and wherein an axial movement of the parts relative to eachother causes irreversible activation of the device such that thedigestor fluid is absorbed by the digestible material liquefying it overa period of time, whereupon the smooth surface is dissipated and a useris able to feel the raised tactile pattern.
 11. A lid as claimed inclaim 10 wherein the base of the tray defines a channel sealed by avalve that is opened on activation of the device.
 12. A lid as claimedin claim 11 wherein the tray is sealed into the cavity to prevent escapeof digestor fluid from the reservoir.
 13. A lid as claimed in claim 12wherein the tray is sealed by a snap fit between the projection and thedevice.
 14. A lid as claimed in claim 10, wherein the two parts rotaterelative to one another in order to axially reduce the spacing betweenthem forcing the digestor fluid out of the reservoir.
 15. A lid asclaimed in claim 14 wherein the base of the tray defines a channelsealed by a valve that is opened on activation of the device.
 16. A lidas claimed in claim 15 wherein the tray is sealed into the cavity toprevent escape of digestor fluid from the reservoir.
 17. A lid asclaimed in claim 16 wherein the tray is sealed by a snap fit between theprojection and the device.
 18. A lid as claimed in claim 10 wherein thereservoir contains a sponge.
 19. A lid as claimed in claim 18, wherein abase of the projection is made of a flexible material having a centralpart for supporting the sponge, and a peripheral inclined wall sectionwhich in a pre-activated condition is downwardly sloping and in anactivated condition is upwardly sloping to compress the sponge.
 20. Alid as claimed in claim 10 wherein a thin layer of absorbent material isprovided underneath the digestible material in order to distributedigestor fluid across the surface of the digestible material.
 21. A lidas claimed in claim 11 wherein a thin layer of absorbent material isprovided underneath the digestible material in order to distributedigestor fluid across the surface of the digestible material.
 22. A lidas claimed in claim 18 wherein a thin layer of absorbent material isprovided underneath the digestible material in order to distributedigestor fluid across the surface of the digestible material.
 23. A lidas claimed in claim 19 wherein a thin layer of absorbent material isprovided underneath the digestible material in order to distributedigestor fluid across the surface of the digestible material.
 24. A lidas claimed in claim 10 wherein the axial movement of the parts can bereversed.
 25. A lid as claimed in claim 11 wherein the axial movement ofthe parts can be reversed.
 26. A lid as claimed in claim 18 wherein theaxial movement of the parts can be reversed.
 27. A lid as claimed inclaim 21 wherein the axial movement of the parts can be reversed.
 28. Alid as claimed in claim 22 wherein the axial movement of the parts canbe reversed.
 29. A lid for closing a container comprising a first parthaving an indentation adapted to receive a projection of a second part,the projection defining a cavity into which a spoilage monitoring deviceis received; the spoilage monitoring device comprising a reservoircontaining a digestor fluid and a tray containing a digestible material,wherein the tray has a base with a raised tactile pattern formed thereonand the digestible material is solid and covers the raised tactilesurface; and wherein an axial movement of the parts relative to eachother causes irreversible activation of the device such that thedigestor fluid is absorbed by the digestible material liquefying it overa period of time, whereupon the digestible material is dissipated and auser is able to feel the raised tactile pattern.